Donald Trump appears set to pull the United States out of the Paris climate agreement

President Donald Trump could pull the United States out of the Paris climate accord Wednesday, Politico and the New York Times report, in what would be a desperate move to show the American people he can make good on campaign promises at a time when his presidency is flailing. The decision is not final yet, though, so stay tuned.

Perhaps more than any of Trump’s policy decisions to date, exiting the agreement carries the risk of widespread and lasting damage — not just to the planet and future generations, but to America’s standing and diplomatic relations with the rest of world.

The accord, which has been agreed to by more than 190 countries and ratified by 147 countries since it was signed in December 2015, established a specific set of tools to help countries cut greenhouse gas emissions over time. Its goal is to hold global warming below 2 degrees Celsius and to avoid the worst risks of a warmer planet, though countries do not appear to be on track to meet its emissions reduction goals.

While it’s certainly not the end-all, be-all scheme to reverse global warming, the agreement is the most comprehensive international effort yet to tackle the climate problem. It’s also been widely hailed as a triumph of diplomacy in the face of what may be the toughest problem humanity has ever encountered.

Yet a select few members of Trump’s inner circle have viewed the agreement as a threat to the fossil fuel industry — and the US economy at large. Trump has been dithering on the decision for months, thanks to a tug-of-war playing out among his advisers. As Vox’s David Roberts has written, we’ve known that the main proponents of leaving the deal were the hardcore nationalists in Trump’s inner circle: Steve Bannon, White House counsel Don McGahn, and committed climate denier EPA Administrator Scott Pruitt.

If Trump decides to leave Paris today, it will reveal that those advisers — as opposed to Ivanka Trump, Gary Cohn, and Jared Kushner, who wanted to keep the US in the agreement — had Trump’s ear on this matter in the end. And this will be devastating, not just for any American who cares about climate change and would like the US to get serious about cutting its emissions, but for every country around the world that’s committed to working together on the problem.

It is also a massive blow to America’s identity as a global leader. As David Victor, an international relations scholar at UC San Diego, told Roberts, “We’re shooting ourselves in the foot. Seventy percent of the damage is going to be to the US.”

Scientists have been warning us for years that a rise in global average temperature more than 2 degrees Celsius will mean widespread stresses on food and water, sea level rise, and conflict and suffering that disproportionately affect the poor.

To try to avert the worst of these threats, countries agreed to dramatically cut emissions as part of the Paris accord. But it is essentially a nonbinding agreement and wasn’t ratified by the Senate. So leaving could be pretty simple, though it will take about four years to formally do it.

In the meantime, US officials could stop participating in climate talks. And Trump could pull out of the underlying UN Framework Convention on Climate Change. That could happen in a just a year’s time and would send the message that the US is pretty much done with international cooperation on climate change.

As for what Trump’s apparent decision will mean for the other major countries in the agreement, here’s Brad Plumer writing for Vox:

China, the world’s largest emitter, would be poised to assume a dominant role in future talks, and its leaders have tended to argue for looser oversight and accountability mechanisms within the deal than the US has. “China has historically been a little more wary of strong international procedures and institutions,” [Victor] told me recently. “You might see the treaty become more decentralized and less formalized over time.”

A bigger concern is that if the US steps back, other countries could decide to scale back their own individual efforts to tackle global warming, says Andrew Light, a former senior climate negotiator at the State Department who is now at the World Resources Institute. “If the US pulls out altogether, the chances increase that developing countries like Brazil or India back away from their own commitments and say, ‘Why should we bother doing this if the world’s biggest historical emitter is completely out of the game now?’” If that were to happen, the chances of avoiding severe global warming would start to look far more dire. ...

There’s also the prospect that the US could face serious diplomatic repercussions for leaving. Europe, China, and other countries could threaten to withhold cooperation on other issues the US cares about. In the most extreme scenario, other countries could threaten to impose carbon tariffs on the US, sparking a trade war. That’s why many Trump allies, like Sen. Bob Corker (R-TN), have argued it would have been smarter to stay in.

There’s still a lot we don’t know about how this will play out. It’s possible that at the last minute, Trump will decide to stay in. He could decide to withdraw, but with caveats. Let’s wait and see.